<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>浏览器版本过低</title>
    <style>
        .upgrade{overflow: hidden;width: 100%;height: 100%;position: absolute;left: 0;top:0;background:rgba(0,0,0,0.9);filter:alpha(opacity=90);}
        .upgrade div{width: 350px;height: 200px;vertical-align: middle;margin: 0 auto;background: #fff;text-align: center;line-height: 200px;font-size: 20px;color: #333;filter:alpha(opacity=100);}
    </style>
</head>
<body>
<div class="upgrade">
    <div>
        当前浏览器版本过低，请升级浏览器
    </div>
</div>
<script>

</script>
</body>
</html>